The present invention relates generally to plastic surgery, more particularly to cosmetic surgery and still more particularly to fat transfer.
Fat transfer, also known as fat grafting, entails two procedures performed in series. In the first fat transfer procedure known as fat harvesting, fat is removed and recovered from one or more fatty sites on the body of a patient, such as the thighs or stomach, by any number of techniques including liposuction or lipoplasty. The harvested fat is a complex, multi-component mixture comprised of mature adipocytes, precursor adipocytes, other precursor cells and lipids from ruptured mature adipocytes. Adipocytes are the primary cells in adipose tissue, which is the loose connective tissue in the body where most fat resides. As connective tissue, adipose tissue also includes fibers and other non-fat material in addition to the adipocytes. Lipids are molecules including fat molecules which may be simplistically characterized as loose fat or fat particles. Harvested fat may be categorized by size as macrofat, microfat or nanofat in descending order of particle size.
In the second fat transfer procedure known as fat injection, the loose fat in the harvested fat is re-injected into the body of the same patient, but into one or more different sites on the body. The re-injected fat increases volume at the treated injection site and enhances the appearance of the patient. Potential injection sites include the face, breasts, cheeks, lips, buttocks, and chin.
Nanofat, as compared to larger fats, has been found to be more desirable for fat re-injection because it produces markedly better results in the ultimate appearance of the patient, particularly when treating superficial dermal layers such as eyelids and the like. Fat transfer practitioners have also found it highly advantageous to use very fine sharp syringe cannulas on the order of about 27-30 gauge when re-injecting harvested fat. The fine cannulas are less invasive and disruptive to the patient and can substantially reduce pain, bruising and/or other undesirable side effects of the procedure while simultaneously shortening patient recovery time. Nanofat, as compared to larger fats, does not substantially clog or otherwise impede flow through these very fine cannulas, thereby additionally rendering nanofat more desirable for fat re-injection. An exemplary fat transfer procedure using nanofat is described in “Nanofat Grafting: Basic Research and Clinical Applications,” Tonnard, Patrick, et al., Plastic and Reconstructive Surgery Journal, v. 132(4), at pp. 1017-26, October 2013, which is incorporated herein by reference.
In view of the above, it has been found desirable to break down and size the harvested fat before re-injecting the fat into the body. One procedure for sizing harvested fat is centrifugation wherein the harvested fat is placed in a conventional centrifuge container such as a test tube and centrifuged. Centrifuging the harvested fat in the container desirably stratifies the harvested fat into discrete layers characterized by their density. The most dense material of the harvested fat resides in a most dense layer which settles to the bottom of the container. The least dense material of the harvested fat resides in a least dense layer which rises to the top of the container. The intermediate density material of the harvested resides in an intermediate density layer which is positioned intermediately between the most and least dense layers. It is often desirable to recover only one of these layers to the exclusion of the other layers for the subsequent fat injection procedure. For example, in some cases the intermediate density material has been found most desirable for the fat injection procedure. Unfortunately, it is often problematic to effectively recover the material of the intermediate density layer from the centrifuge container without contaminating this material with the material from the adjoining most and/or least dense layers.
The present invention recognizes a need for an apparatus and method which facilitates the stratification of harvested fat into more desirable material and less desirable material and which enables the practitioner to effectively and efficiently recover the desirable material from the harvested fat without contamination from the less desirable material while maintaining the system for stratification and recovery of the harvested fat anaerobic and closed to the external environment. Accordingly, it is an object of the present invention to provide an apparatus and method which satisfies the above needs. It is more generally an object of the present invention to provide an apparatus which enables the reconfiguration of a conventional syringe to a sealed fluid reservoir having utility, for example, as a sealed fluid storage and/or processing container. It is another general object of the present invention to provide a method for reconfiguring a conventional syringe to a sealed fluid reservoir having utility, for example, as a sealed fluid storage and/or processing container. It is more particularly an object of the present invention to provide an apparatus which enables the reconfiguration of a conventional syringe to a sealed fat processing container and, more particularly still, to a sealed centrifuge container. It is another more particular object of the present invention to provide a method for reconfiguring a conventional syringe to a sealed fat processing container and, more particularly still, to a sealed centrifuge container. These objects and others are accomplished in accordance with the invention described hereafter.